The present invention relates to a construction for suspension system mounting portions of the body of a vehicle.
Suspension system mounting portions of the monocoque-structured body of a vehicle are generally provided on a cross member having a closed hollow cross-section formed by assembling sheet materials that are pressed into shapes.
According to the above construction, however, since the suspension system mounting portion is formed using a plurality of relatively thin sheet materials, in order to secure a sufficient rigidity, the configurations of members constituting the cross member tend to become complicated, and this directly leads to complicated production processes.
Although a sub-frame system is known in which the support portions of the suspension systems are provided separately from the body of the vehicle, even with this system, it is inevitable that the weight and production costs of the vehicle increase.
The present invention was devised to solve the inconvenience inherent in the prior art described above, and a main object thereof is to provide a construction for suspension system mounting portions of the body of a vehicle which is simple and provides high rigidity.
The above-mentioned object can be achieved by a construction for suspension system mounting portions of the body of a vehicle, according to the present invention, comprising a closed cross-sectional portion, an extruded beam member and a die-cast suspension arm bracket member. The closed cross-sectional portion is extended in a transverse direction of the body of the vehicle and is formed with a plurality of sheet materials which are each pressed into shapes. The extruded beam member is extended into the interior of the closed cross-sectional portion in the transverse direction. The die-cast suspension arm bracket member is welded to an external surface of the closed cross-sectional portion and has a protruding part. The protruding part is protruded into the interior of the closed cross-sectional portion and is welded to the extruded beam member.
In addition, with a view to attaining the aforesaid object, according to the invention, there is provided a construction for suspension system mounting portions of the body of a vehicle characterized in that a closed cross-sectional portion extending in a transverse direction of the body of the vehicle is formed with a plurality of sheet materials (for example, a front dash panel and a dash panel lower cross member) which are each pressed into shapes, that an extruded beam member (as a reinforcement beam) is caused to extend into the interior of the closed cross-sectional portion, die-cast suspension arm brackets are welded to an external surface of the closed cross-sectional portion with apart thereof (for example, protruding portions) being caused to protrude into the interior of the closed cross-sectional portion, and that the beam member is welded to the protruding portions.
With this construction, high rigidity can be obtained without resulting in the complexity in shaping the respective constituent members of the closed cross-sectional portion formed with the sheet materials which are pressed into shapes by disposing the beam member formed of the extruded material in the interior of the closed cross-sectional portion. In addition, the breaking strength against repeated stress of the suspension system mounting portion can further be improved by a combination of the pressed members having high toughness and the die-cast members having high rigidity.